Feedback and Feed-Forward for Promoting Problem-Based Learning in Online Learning Environments

Purpose - The study aimed to (1) review the literature to construct conceptual models that could guide instructional designers in developing problem/project-based learning environments while applying effective feedback strategies, (2) use the models to design, develop, and implement an online graduate course, and (3) assess the efficiency of the models. Method - Quantitative and qualitative data were gathered during the implementation of an online graduate-level course that was designed and developed using the two proposed conceptual models. Eleven students were enrolled in the course. Multiple sources of data and analytical strategies were used to collect, analyze, and interpret the data. Findings - The results show that the characteristics and strategies suggested in the proposed models supported student achievement in course projects and activities. The timely and frequent feedback allowed students to make necessary changes to their final project parts and improve performance. The motivating, informative/ specific feedback and feed-forward goals appeared to provide a reference for areas of student improvement. A balance of the three types of feedback, along with metacognitive questioning, supported student improvement. Because the frequency of feedback was dependent upon student request, those who needed more frequent feedback during the acquisition of learning benefited from that, but those who did not need it received the moderate amount necessary to be successful. Significance - The study brings to light the importance of three types of formative feedback in problem or project-based learning. It offers two conceptual frameworks for instructional designers and curriculum developers. The models could be used to provide all forms of feedback including feed up, feedback and feed-forward to support student success in PBL learning environments

Telomere shortening associated with increased levels of oxidative stress in sulfur mustard-exposed Iranian veterans

Sulfur Mustard (SM) is the most widely used chemical weapon. It was used in World War 1 and in the more recent Iran-Iraq conflict. Genetic toxicity and DNA alkylation effects of SM in molecular and animal experiments are well documented. In this study, lymphocytic telomere lengths and serum levels of isoprostane F2α were measured using q-PCR and enzyme immunoassay-based methods in 40 Iranian veterans who had been exposed to SM between 1983-88 and 40 non-exposed healthy volunteers. The relative telomere length in SM-exposed individuals was found to be significantly shorter than the non-exposed individuals. In addition, the level of 8-isoprostane F2α was significantly higher in the SM-exposed group compared to controls. Oxidative stress can be caused by defective antioxidant responses following gene mutations or altered activities of antioxidant enzymes. Chronic respiratory diseases and infections may also increaseoxidative stress. The novel finding of this study was a the identification of ‘premature ageing phenotype’. More specifically, telomere shortening which occurs naturally with aging is accelerated in SM-exposed individuals. Oxidative stress, mutations in DNA repair genes and epimutaions may be among the major mechanisms of telomere attrition. These findings may help for a novel therapeutic strategy by telomere elongation or for validation of an exposure biomarker for SM toxicity

Effect of citalopram and sertraline on the expression of miRNA- 124, 132, and 16 and their protein targets in patients with depression

Objective(s): This study aimed to evaluate the effect of SSRIs on the expression of miRNAs and their protein targets.Materials and Methods: In a 100 day open-label study of citalopram (n=25) and sertraline (n=25), levels of miRNA 16, 132, and 124 and glucocorticoid receptor (GR), Brain-derived neurotrophic factor (BDNF), and serotonin transporter (SERT) protein expression were measured by QRT-PCR and western blot in healthy control (n=20), patients with depression at the baseline, and same patients after 100 days of treatment.Results: Expression levels of GR and BDNF proteins were lower in the depressed group before treatment as compared with the healthy group (P<0.0001). The SERT level was higher among the depressed group before treatment in comparison with the healthy group (P<0.0001). The level of GR and BDNF significantly increased, and SERT expression decreased after receiving sertraline (P<0.05). When the depressed group received citalopram, only SERT and GR were altered (P<0.05). Among the microRNAs’ expression investigated, mir-124 and mir-132 were higher, and mir-16 was lower among the depressed compared with the healthy group (P<0.0001). Individuals receiving citalopram only showed an increase in the expression of mir-16 while administration of sertraline led to a significant increase in the expression of mir-16 and a decrease in mir-124 and mir-132 (P<0.05).Conclusion: This elucidated the relationship between antidepressant treatment and the expression of different microRNA that control gene expression in various pathways involved in depressed patients.  Receiving SSRI can affect the level of these proteins and their relevant microRNAs

Constructivism in theory and practice: Toward a better understanding. The High School Journal.

Abstract Although constructivism is a concept that has been embraced my many teachers over the past 15 years